A liquid crystal panel used in a liquid crystal display device, such as a liquid crystal television set, does not emit light by itself. Thus, the liquid crystal panel uses a backlight unit as a separate lighting device. This backlight unit is installed on a back side (on a side opposite to the display surface) of the liquid crystal panel and includes: a chassis having an opening on the liquid crystal panel side; alight source housed in the chassis; and an optical member (such as a diffuser sheet) arranged at the opening of the chassis for causing the light emitted from the light source to be efficiently output toward the liquid crystal panel side.
In the backlight unit of the above configuration, in order to reduce power consumption, for example, an LED may be used as a light source, as described in Patent Document 1 indicated below. The example according to Patent Document 1 includes a flexible wiring board (LED board) on which the LED is mounted, and a light guide plate that guides light from the LED toward an optical member. The flexible wiring board is retained by a retaining structure configured to be locked on both of the LED and the light guide plate.
Patent Document 1: Japanese Unexamined Patent Publication No. 2007-234375